Suppose the real valued [tex]g[/tex] is defined on [tex]\mathbb{R}[/tex] and [tex]g'(x) < 0[/tex] for every real [tex]x[/tex]. Prove there's no differentiable [tex]f: R \rightarrow R[/tex] such that [tex]f \circ f = g[/tex].(adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: Prove there's no differentiable f such that f(f(x)) = g(x) with g'(x) < 0 for every x

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